This Bible contradiction is from the Skeptic's Annotated Bible.
1 Thessalonians 4:15-17 View context
For this we say unto you by the word of the Lord, that we which are alive [and] remain unto the coming of the Lord shall not prevent them which are asleep.
For the Lord himself shall descend from heaven with a shout, with the voice of the archangel, and with the trump of God: and the dead in Christ shall rise first:
Then we which are alive [and] remain shall be caught up together with them in the clouds, to meet the Lord in the air: and so shall we ever be with the Lord.
1 Thessalonians 5:23 View context
And the very God of peace sanctify you wholly; and [I pray God] your whole spirit and soul and body be preserved blameless unto the coming of our Lord Jesus Christ.
2 Thessalonians 2:2-3 View context
That ye be not soon shaken in mind, or be troubled, neither by spirit, nor by word, nor by letter as from us, as that the day of Christ is at hand.
Let no man deceive you by any means: for [that day shall not come], except there come a falling away first, and that man of sin be revealed, the son of perdition;